Conductive surfaces have several applications in medicine. For example, cardiac pacemakers have conductive surfaces that transfer electrical pulses to the heart to stop unwanted electrical activity in the conduction fibers of the heart. Additionally, it is well known that electrical fields applied to nerves, muscles, vessels and the like can stimulate the corresponding nerves, muscles, vessels or other tissue.
Recently, new, potential, uses for the conduction of electricity in medical contexts have been developed. For example, in Shocking Treatment Proposed for AIDS. (zapping the AIDS virus with low-voltage electric current), 139 SCIENCE NEWS 207 (1991), methods to reduce infectivity of viruses by applying a current, e.g. in the range of about 50 to 100 .mu.amps, to white blood cells containing the virus exist. The current is believed to affect the virus such that production of enzymes crucial to virus reproduction is inhibited.
Application of an electric pulse to fluids to sterilize the fluid is also known. In particular, Viazurek et al., Effect of Short HV pulses on Bacteria and Fungi, 2 EEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION 418 (1995) discloses use of electrical pulses to sterilize consumable fluids, which may either be ingested by or inserted into a patient.
Another medical application is the electrical sterilization of biofilms (e.g., biofilms which form on a dialysis membrane away from an electrode). Wellman et al., Bacterial Biofilms and the Bioelectric Effect, 40 ANTIMICROB AGENTS CHEMOTHER 2012 (1996) discloses increased efficiency of sterilizers, such as antibiotics and biocides, by the addition of an electric field. Thus, in the presence of an effective electrical field, less sterilizer is required to kill unwanted bacteria and may therefore reduce the risk of antibiotic resistance.
Application of electrical current may also be used to simulate growth of certain bacteria. As disclosed in Using Electricity to Kill Bugs, 18 EPRI JOURNAL 4 (1993), this technique may be used for, inter alia, production of genetically engineered substances. Alternatively, this technique could be used to breed beneficial bacteria within a body. Additionally, it is thought that small electrical fields can attract or repel various pathogens or bacteria from an area which includes the electrical field.
Use of electricity to generate local heat is also known. In this regard, application of localized heat within a body can have a therapeutic effect. Accordingly, placing resistive or conductive materials within the body and passing a current through such materials to generate heat to the body region of interest can have therapeutic value. In addition, extreme local heat may be used to cauterize or remove unwanted material. Removal of unwanted material is assisted by destroying, burning, or reducing a volume of unwanted material, making removal of such material through a relatively small opening possible. For example, unwanted plaque or cholesterol may be removed using this technique.
The above and other medical applications generally are accomplished by electrically connecting sensors inside a body to instruments outside a body, or by the invasive insertion of rigid electrodes into a patient, or by the addition of electricity to a device, such as a container, filled with a material to be treated. Each of these methodologies have various drawbacks.
For example, invasive insertion of rigid electrodes is problematic because, inter alia, the insertion may increase the risk of infection to the patient. Additionally, insertion of a rigid electrode may cause discomfort to the patient during and/or after insertion.
Similarly, medical applications involving the external use of electricity (for example, to grow or inhibit growth of certain bacteria) often require multiple components, for example, an electrode which is attached to a device (e.g., a container) to hold the material to be treated. As a result, the apparatus is typically complex and, because of the extra components, extra surface area must be sterilized prior to use, thus, tendering increased costs associated with the procedure.